Apparatus and method for controlling sewing machine

Abstract

A sewing machine having a motor drive operating in response to a controller to rotate in forward and reverse rotation directions. A jogging angle may be set and the drive operated automatically for rotation in forward and/or reverse directions as a function of various operating conditions so that the needle is stopped in an optimum position for piercing a material.

What is claimed is: 
     
       1. A sewing machine controlling apparatus comprising: reversible sewing machine drive means for driving a sewing machine pulley in forward and reverse directions and for moving a needle at least between UP and DOWN positions;   thread trimming means for providing a thread trimming operation;   control means for controlling said sewing machine drive means and said thread trimming operation;   needle position detection means for detecting the needle position of said sewing machine;   jogging angle setting means for setting a jogging angle of said sewing machine pulley, and   means for operating said thread trimming means in response to a jogging signal, and for controlling forward rotation of said sewing machine pulley after the needle position of said sewing machine has reached an UP position, wherein said sewing machine pulley is rotated until said jogging angle set by said jogging angle setting means is reached.   
     
     
       2. A sewing machine controlling apparatus comprising: sewing machine drive means for driving a sewing machine pulley;   control means responsive to a plurality of signals, including a jogging signal, for controlling said sewing machine drive means;   needle position detection means for detecting the needle position of said sewing machine;   rotary angle setting means for setting the rotary angle of said sewing machine pulley;   means for measuring the rotary angle of said sewing machine pulley in response to said needle position detection means; and   means for rotating said sewing machine pulley in response to an angle storage signal entered into said control means, and when a jogging signal is entered, rotating the sewing machine pulley forward to stop at a set jogging angle if the measured rotary angle of said sewing machine pulley is less than a predetermined value and transferring said measured rotary angle of said sewing machine pulley to said rotary angle setting means if the measured rotary angle of said sewing machine pulley is equal to or more than said predetermined value.   
     
     
       3. A sewing machine controlling apparatus comprising: sewing machine drive means for driving a sewing machine pulley;   control means responsive to a plurality of signals, including an ultra-low speed input signal, for controlling said sewing machine drive means;   needle position detection means for detecting the needle position of said sewing machine;   rotary angle setting means for setting the rotary angle of said sewing machine pulley; and   means for measuring the rotary angle of said sewing machine pulley in response to said ultra-low speed input signal entered into said control means and transferring the measured rotary angle of said sewing machine pulley to said rotary angle setting means.